Genetic and metabolic contributions of articular chondrocytes to degenerative joint disease and disturbed skeletal growth, that cannot be readily studied using whole cartilage, are approached by cell culture. Valid conditions have been worked out for synthesis of sulfated glycosaminoglycans and Type II collagen in rabbit but not yet in human cells. These procedures will be applied to inherited rabbit chonrodystrophies while satisfactory culture conditions will be sought for human chondrocytes. Immunofluorescent means will be employed to determine whether two cohorts of chondrocytes are responsible for the mixed molecular species of collagen in monolayer culture of chondrocytes. The mechanism of a putuitary glycoprotein-associated chondrocyte growth factor will be further elaborated.